Currently, this will also print the symbol table after completion

To use:

    python run.py < test_cases.txt

Example:

    (if (or true false) (println "True!"))
    ['if', ['or', 'true', 'false'], ['println', '"True!"']]

    (while true (println "Looping"))
    ['while', 'true', ['println', '"Looping"']]